• 연구논문집
• /
• 통권34호
• /
• pp.87-99
• /
• 2004

A spring tension control device is used as a very important part of an twister system. The friction force of tensioner must keep same friction force during winding in package. For satisfy this function, many device used common compression coil spring. In this paper, by using the case-building technique which was based on simple theory that unknown design variables are induced by given input design variables by the designer, design automation algorithm about rectangular section compression springs with elastic characteristic is developed. Four design equation are justified in using of analysis of torsion of straight bar of rectangular section and geometrical condition of coil spring. Four design equation and nine design variables are computed by case-building technique.

• 한국주거학회논문집
• /
• 제7권1호
• /
• pp.117-126
• /
• 1996

The purpose of this paper is to develop formal design principles towards flexible house plan. A flexible house plan accomodates spatial requirements corresponding to change of life style and provides a way of saving architectural materials. Design properties as a basis for manipulation of room includes adjacency, orientation and geometrical information which are suited well to flexible design. This paper has developed a formal grammar of shape which can be utilized to transform house plan. Flexible design presented here is based on the idea of various operations of the shape grammar. The shape grammar, as a set of rules, specifies manipulations of shapes for reorganization of spatial relationships of rooms in a house plan. It lists exemplary rules in control knowledge which guides design processes for modifying a plan. An example taken from house plan design is used to ilustrate important aspects of the flexible design which fundamentally provides the basis for architectural material saving.

• 한국유체기계학회 논문집
• /
• 제12권3호
• /
• pp.7-12
• /
• 2009

In this paper, shape optimization based on three-dimensional flow analysis has been performed for impeller design of centrifugal compressor. To evaluate the objective function of an isentropic efficiency, Reynolds-averaged Navier-Stokes equations are solved with SST (Shear Stress Transport) turbulence model. The governing equations are discretized by finite volume approximations. The optimization techniques based on the radial basis neural network method are used for the optimization. Latin hypercube sampling as design of experiments is used to generate thirty design points within design space. Sequential quadratic programming is used to search the optimal point based on the radial basis neural network model. Four geometrical variables concerning impeller shape are selected as design variables. The results show that the isentropic efficiency is enhanced effectively from the shape optimization by the radial basis neural network method.

• 대한가정학회지
• /
• 제50권1호
• /
• pp.29-39
• /
• 2012

The purpose of this research is to suggest a scarf design which reflects the traditional culture native to Korea by making use of the combined pattern of jokgakbo patchwork and ddeoksal(rice cake). For research methodology, the computer design programs of Adobe Illustrator CS3 and Adobe Photoshop CS3 were used along with the related literature. For the combined sets of motif pattern, the following were consider: first, a combination of jogakbo in square shape and chrysanthemum in a rice cake mold; second, a combination of radius jogakbo and geometrical pattern; third, a combination of vertical and horizontal forms of jogakbo and rice cake pattern; fourth, a combination of yeouijumunbo and butterfly pattern in rice cake mold. For the scarf design with these applications, technical skills such as repeat, rotation, symmetry, free setup, and distortion were used for the combination motif. In terms of the shape of the design, there are two, square and lengthwise tetragons.

• Journal of Mechanical Science and Technology
• /
• 제20권6호
• /
• pp.770-781
• /
• 2006

This paper defined design constraints for the compound CVTs (continuously variable trans-missions) by combining power-circulation-mode CVTs and power-split-mode CVTs, which were proposed for connecting 2K-H I-type differential gear to V-belt-type CVU (Continuously Variable Unit). The design constraints are the necessary and sufficient conditions to avoid geometrical interferences among elements in the compound CVTs, and to guarantee smooth assembly between the power-circulation-mode CVT and power-split-mode CVT Two com-pound CVTs were designed and manufactured in accordance with the design constraints. With these compound CVTs, theoretical analysis and performance experiments were conducted. The results showed that the design constraints were valid and effective design method, and that the designed compound CVTs had the improved performance.

• 한국실내디자인학회논문집
• /
• 제11호
• /
• pp.57-63
• /
• 1997

In the early 20'c, scientific thoughts make a change the absolute and separate concept of space-time into relative concept of continual entity; a kind of ideal world. It suggests that the meaning of geometry as absolute truth with which has endowed human beings would changed to a relative meaning of accumulation in intellectual work on 'nature'. This cognitive changes appeared into absolute arts in 20'c like Cubism, Superematism or Constructivism. De Stijl movement which had recepted the relative concepts like Einstein's 'theory of relativity' as a developed thought from Newton-Cartesian cognition on the world. Abstration would be adequate method for expressing the dynamics and interrelationship between forms and for giving values to indivisual elements in a compositiov. This method had appeared Modern architectural form, as a common framework. The expression characteristics of geometrical design in Deconstructive and Experimental architecture were summerized in four features through the results of the analysis. First, the relation of architectural element and intertextuality is expressed in discontinuation of context and refusal of functional building. Second, the concept of trace expresses as connection of place, decomposing of excavation of trace, trace of axis, trace of fragments. Third, anti-gravity expression is there to express of open cubic, to outgrow of rectangular system, to outgrow of volume, to separate of ground connectiov. Fourth, the complex composition of abstracted geometric form is these to abstracted geometry about indefinite shape, to layer through the overlap and collage, to de-meaning and amusement of form through the pursuit of uncertainty, to indeterminate of formal meaning through operation and composition of similar form cause to the diverse of meaning.

• 한국실내디자인학회논문집
• /
• 제21권2호
• /
• pp.35-45
• /
• 2012

The development of digital media made the change of architectural paradigm from tectonic to the surface and pattern. This means the transition to the new kind of materiality and the resurrection of ornament. This study started as an aim to apply biological pattern to architectural design from the new perception of pattern. Architectural patterns in the early era appeared as ladders, steps, chains, trees, vortices. But since 21st century, we can find patterns in nature like atoms and molecular structures, fluid forms of dynamics and new geometrical pattern like fractal and first of all biological patterns like viruses and micro-organisms, Voronoi cells, DNA structure, rhizomes and various hybrids and permutations of these. Pattern became one of the most important elements and themes of contemporary architecture through the change of materiality and resurrection of ornament with the new perception of surface in architecture. One of the patterns that give new creative availability to the architectural design is biological pattern which is self-organized as an optimum form through interaction with environment. Biological patterns emerge mostly as self-replicating patterns through morphogenesis, certain geometrical patterns(in particular triangles, pentagons, hexagons and spirals). The architectural application methods of biological patterns are direct figural pattern of organism, circle pattern, polygon pattern, energy-material control pattern, differentiation pattern, parametric pattern, growth principle pattern, evolutionary ecologic pattern. These patterns can be utilized as practical architectural patterns through the use of computer programs as morphogenetic programs like L-system, MoSS program and genetic algorithm programs like Grasshoper, Generative Components with the help of computing technology like mapping and scripting.

• Tribology and Lubricants
• /
• 제35권5호
• /
• pp.286-293
• /
• 2019

In friction and wear tests that use friction force microscopy (FFM), the wear debris transfer to the tip apex that changes tip radius is a crucial issue that influences the friction and wear performances of films and coatings with nanoscale thicknesses. In this study, FFM tests are performed for bilayer $MoS_2$ film to obtain a better understanding of how geometrical and chemical changes of tip apex influence the friction and wear properties of nanoscale molecular layers. The critical load can be estimated from the test results based on the clear distinction of the failure area. Scanning electron microscopy and energy-dispersive spectroscopy are employed to measure and observe the geometrical and chemical changes of the tip apex. Under normal loads lower than 1000 nN, the reuse of tips enhances the friction and wear performance at the tip-sample interface as the contact pair changes with the increase of tip radius. Therefore, the reduction of contact pressure due to the increase of tip radius by the transfer of $MoS_2$ or Mo-dominant wear debris and the change of contact pairs from diamond/$MoS_2$ to partial $MoS_2$ or Mo/$MoS_2$ can explain the critical load increase that results from tip reuse. We suggest that the wear debris transfer to the tip apex should be considered when used tips are repeatedly employed to identify the tribological properties of ultra-thin films using FFM.

• 한국실내디자인학회논문집
• /
• 제21호
• /
• pp.121-128
• /
• 1999

The purpose of this study is to provide practical guide for the Preference of exterior design in Apartment. The data is collected through questionnaire survey including observations and interviews. The sample consists of 229. The data is analyzed by using SPSS-PC. The major findings are as follows. (1) Most of residents recognize the importance of exterior design of apartments. (2) Most of residents are satisfied with the exterior design such as building form, color, and material and not satisfies with environment of apartments. (3) The most preferred color of Apartment is white as primary color and green as secondary color. (4) The most preferred color pattern is vertical type as facade, horizontal type as the back wall, super graphic and geometrical type as the side wall. (5) The preferred exterior images are modern, simple, and unique style.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2005년도 춘계학술대회 논문집
• /
• pp.1652-1655
• /
• 2005

All teeth on the cycloidal plate gear exist in the contact motion with rollers and the forces are interacted between roller gears with cycloidal plate gears. So, the contact forces and friction forces must be required to improve the accuracy in design procedures of cycloidal speed reducers. This paper presents a force analysis considered the friction effect approach derived by static force equilibrium condition, geometrical adaptation, instant velocity center method and relative velocity method. Finally, the paper develops CAD-program for the construction of the design automation using the proposed method.